1. Field of the Invention
This invention concerns strings particularly suitable for use in game rackets such as tennis and squash. More particularly, the strings are comprised of large monofilaments which are ply-twisted and bonded together.
2. Description of the Prior Art
Racket strings made of synthetic monofilaments in a wide variety of constructions are commercially available. A rather common construction is one having a very large central monofilament completely surrounded by a spiral wrapping of one or two layers of many smaller monofilaments, for example, from 11 to 35 or more of the smaller monofilaments. Another type of known string construction is represented by Crandall in U.S. Pat. No. 3,738,096 which discloses a string formed from three strands which have been twisted individually in the first direction and ply-twisted in the opposite direction and coated with a plastic material. The resulting undulating string surface is taught to impart more effective spin to the ball when struck with the racket.
In spite of many available strings of synthetic filaments, many top ranking players still prefer the playing properties of strings made from natural gut, for example, from twisted bundles of fine strips of sheep gut, even though they tend to be less durable than strings of synthetic filaments. Consequently, there is a continuing need for new and improved racket strings made from synthetic filaments.